The present invention generally relates to an electrolytic cell for the generation of low cost halogen biocidally active agent for the treatment of a sewage or other liquid effluents especially those waters of a fresh water swimming pool or cooling towers. More particularly, the present disclosure relates to an improved electrolytic cell having a bipolar configuration which is used in line with the pumps generally associated with the distribution of waters in swimming pools or cooling towers or other liquid effluents for the generation of chlorine from effluent containing low levels of chloride. This employs an enclosure connected in line with the liquid distribution system of the facility containing a series of parallel planar plates to be utilized as electrodes arranged such that the effluent flows through the parallel planar matrix of plates and is treated thereby with the chlorine being electrolytically produced from within the confines of the electrolytic cell.
Chlorine has been used for some time as a biocidally active agent for use with sewage, liquid effluents, water in swimming pools or cooling tower waters, in addition to drinking water. In the past this has been done largely with chemical treatment of such waters with chemical compounds such as a hypochlorite compound. The addition of chemical compounds to affect the biocidal activity desired has become costly and it is likely that greater restrictions upon the traffic of dangerous chemical products in the transportation networks of the world will necessitate on site manufacture of such compounds or a different means by which treatment may be carried out. Electrochemical methods of manufacture present one solution to this problem due to their capability for small onsite production at a reasonable cost, greater ecological acceptability, and potential for energy conservation. Furthermore, electrochemical methods of manufacture can generally be operated as a closed system thereby allowing greater control over the escape of by-products or waste products from the electrolytic cells which may have been environmentally undesirable. Electrolytic cells promise to be one of the most efficient means of utilizing electricity which is likely to be used more in the future due to the rapidly rising price and expected exhaustion of fossil fuels such as coal, gas, and oil.
Where there are readily available supplies of salt water such as sea water, aqueous solutions of hypochlorite solution can be readily made by electrolysis of sea water. All too often though electrical generation facilities, swimming pools, or sewage treatment plants are located in areas where only fresh water is available. In these settings, electrolytic generation of low levels of chlorine has been hampered by low current efficiencies and the formation of scale upon the cathode. Therefore, those skilled in the art have turned to a system whereby much higher concentrations of a chloride solution are used to generate chlorine which is then admixed with the liquids for use in the biocidal treatment of the liquids. While current efficiencies are good in such units, the associated hardware for the admixing step of the procedure becomes increasingly expensive and thus lowers commercial realization of the full potential of electrolytic chlorine generation for such treatment purposes. Also such units have become increasingly complex and have thus far exhibited poor field experience in use.
Therefore it would be exceedingly advantageous to develop an electrolytic cell system for the generation of chlorine using a liquid electrolyte containing very low concentrations of halogen salt such that the device could be used in line with the pumping system of the facility.